The present invention relates to valve having an improved structure for sealing and affixing a cover on a valve body. More specifically, this invention relates to an improved valve structure for assuring proper positioning of a seal between a cover and a valve body so that the seal will perform correctly over the life of the valve.
There have been proposed various structures for sealing a cover and a valve body without the use of gaskets and affixing a cover to a valve body without the use of nuts and bolts. The U.S. Pat. No. 4,431,163, discloses a valve body 2, valve cover 3, O-ring seal 24 and locking elements 28. U.S. Pat. No. 4,251,054 discloses a valve body 1, valve cover 2, sealing ring 17 with apron 18, and annular locking spring 15.
With the structures of the foregoing patents, there will be an undesirable uncertainty in assembling the valve in terms whether or not the seal member or members are properly positioned for long term use in these structures.
It is, accordingly an object of this invention to provide a definite indication of the proper positioning of the sealing member so that when the valve elements are assembled at a site, the user will be able to determine with a high degree of accuracy whether or not suitable sealing has been achieved.
The present invention is directed not only towards eliminating the deficiencies in the above-mentioned prior art, but also towards providing an improved valve body and method of manufacture thereof.